Impact device



oct. 11. 1927.

- 14,645,477 N. G EORGEVITCH IMPACT DEVICE Filed May 12, 1925 l 2 Sheets-Sheet 1 Figi 32 'Iii 11 l Y jf 6'@ @life v U'cja/ IMPACT DEVICE Filed May 1g' '1925 Fig. 5 h

l l l .2 Sheets-Sheet 2 y IHH Patented Oct. 11, 1927.

1,645,477 EFICE.

NICOLAS GEORGEVITCH, or PARIS, FRANCE.

Application led May `12, 1923, Serial No. 638,575, and in France January 22, 1923.

The invention consists inan improvement in or modification of the impact device claimedv in specification No. 611,884, dated the 10th day of January, 1923, characterized by the feature that the weights are restrained f and released by a cam device, guide members on the weights being adapted to contact with the cam device.

The invention also consists in other details and arrangements hereinafter described and indicated. A

The accompanying sheet of drawings illustrates solely by way of example a constructional form of this invention.

Figures 1 and 2 are respectively a section 25 on the line I-I of Figure 2, and a view, partly in section, on the line II-II of Fig-V- ure 1 andV partly in elevation of a rotary hammer workedby centrifugal force.

Figure 3 is a section on the line III- 111 of Figure 1, of a portion of this hammer.y Y

Figure 4 is a section on the line IV-IV' of Figure 2, of a portion of this hammer,

certain parts of the said hammer` beingy shown in a different position.

Figure 4 is a section showing the joint between the levers and 26 of Figures 1 and 4. n p

YFigures 5 and 6 are respectively a section on the line VV of Figure 6, and a section on the line VI-VI of 'Figure 5, of an arrangement for controlling the rotation of the tool.

Figure 7 is a section on the line VII-VH of Figure 5 of a detail of this arrangement force comprises a casing 1 having two fiat ends 2 and` 3 and a cylindrical wall 4, the flat walls 2 and 3 comprising annular bearing sockets 5 and 6 which are concentric with the said fiat ends and in which a shaft 7 is mounted on ball bearings and ball thrust bearings. s 0n the shaft 7 there is fixed a member'8 comprising two symmetrical sockets 9, in r each of which is mounted a weight 10. On

the bearing 5 mounted a plate .ll which The rotary ham-mer worked by centrifugal bears against the outer face of the wall 2, a cam 12 being pivoted at one end on a pivot pin 13 mounted in the plate 11, while the other 'end of the cam carries a stud 14 engagingv in a slot 15 formed in the platev 11, having the shape of an arc of a. circley and having itscentre on the pivotal axis of the cam. Each weight is traversed by a rod 1G carrying a roller 17 which is adapted to come into contact with the cam during the rotation of the shaft 7, the sockets 9 having apertures 18 for the passage of the ends of t-he rods 16.

The casing comprises a sleeve 19 in which is mounted a tool holder mandrel 20, which comprises a collar 21on which rests the end of a push-bolt This bolt 22 is mounted in a socket 23-fixed to the sleeve 19. The casing is providedwith a lug 24 'on which are pivotedl a lever 25, one end of which rests lupon the push-bolt 22, and a lever 26,

one end of which bears against the cam 12.l

The two levers are connected by a pivotal joint which allows them a certain amount of play. The shaft 7 receives its motion by suitablemeans, and during the rotation the weights lare moved away from the axis of rotation by centrifugal' force. When the weights reach the cam, they move nearer to the axis of rotation, and on arriving at the end of the cam they are suddenly released, and strike with force the tool holder mandrel. f

The vplate 11 is provided with a rod 27 engaged in a slot 28 in the casing, which allows of shifting the plate angularly with the object of moving the cam nearer to or away from the tool holder sleeve, and at the same time of moving the end of the cam, which carries the stud 14, nearer to or away from the axis of rotation. This device al- 'lows of so regulating the apparatus as to cause the weights to strike always upon the toolholder mandrel whatever may be the plate llin any position in which it may be adjusted.

The apparatus is provided with a handle 3() which can be held in one hand'. This handle can be lengthened to such an extent as will enable it to be held with both hands at once by means of tivo extensions 3l arranged one on each side of the handle' 3() in the prolongation of the latter, such extensions, being secured by means of a bolt 32 Which extends through the handle and through the two extensions.

The apparatus is also provided with a bent rod pivoted to a lever 34, the axis of i which is mounted in a bracket 35 formed in one piece with the casing. This lever is in contact with apush-bolt 36 which is mounted in a socket 37 fixed to the sleeve 19 and is itself in contact `With the'collar 2l. The free end of the rod 33 is conveniently arranged along one of the extensions 31, and by exerting pressure upon this rod With the hand that holds the sai-d extension, the operator moves d-oivn the push-bolt 36, which by bearing upon the. collar 2l, causes the mandrel 2O to descend to a point Where the pu'slrbolt 36 is locked by a'lo'clring bolt 38 engaging in a recess 39 in the push-bolt 36.

The descent of the mandrel 20 allows of the descent of the push-bolt 22, thus disengaging the latter from the lever 25, which in its turn ceases to act uponV the lever 26. This lever 26 no lonOer exerts an ressure u on b the cam l2 Which is then pushed by the Weights against the c ylindrical Wall of the casing (Figure 4). The result of this new position of the parts is that the Weights no longer strike the mandrel, and the hammer then revolves idly, this arrangement allowing of interrupting the vvorlr Without stop# ping the motor.

Tn the ease Where it is desired that the apparatus should be able to Worl With a rotating tool, the said apparatus is provided with a mechanism adapted to transmit the motion of the shaft 7 to the tool. This mechanism may, for instance, comprise a shaft 40 parallel to the'axis of the mandrel and carried by a. bearing 4l formed in one' piece With one of the flat sides of the casing. This shaft is connected to the tool 42 vby means of gear 43, and on the shaft is mounted a pinion 44 provided with a. sto} ibolt 45 ivliich allows of fixingthe said pinion tothe sha-ft in tvvo different positions according as this stop-bolt is engaged in one or other of tivo notches 46 and 7 formed in the shaft. Y

On the shaft 7 there isfixed a plate 48, vi'vhich :is provided with holes 49 Whose c-entres are spacedon a circumference concentric With the plate, the distance between the centres of tivo consecutive holesbeing equal to the pitch of the pinion 44, While the 'teeth nf the said' piiibn are adapted; to 'engage in the holes 49. The plate 48 comprises furrther tvvo holes 50 which are of the same size as the holes 49 and are symmetrical relatively to the axis of the plate. The holes 50 are separated by two arc-shaped slots 46, the teeth of the pinion 44 are in mesh With the holes 50 and slots 5l. In this case, which is applicable to drilling machines, the plate drives the pinion only through the length of one pitch at each half revolution of the plate. Consequently the rotation of the pinion is intermittent. When the stopbolt is engaged in the notch47, th-e teeth of the pinion 44 are in mesh With the holes 49, and in this case, Which-is applicable to borers and todrilling machines, the rotation of the pinion isA continuous. It Will beV understood that the pinion 44 is slidable upon the shaft 40 so that it may be displaced by hand when necessary to cause it .to mesh either with thev holes 49 or with the holes and slots 50, 51. Tn order to permit of the disengagement of the pinion 44 from the Wheel 48 for the purpose ofy enabling the sliding` adjustment to be made upon the shaft 40 the upper end of the shaft 49 should be moved outwardly (toVv the right in Figure 5) or if sufficientrooinbc left for the purpose on the shaft 7 `the Wheel 48 may be displaced inwardly (to the left in Fig- 'ure 5) the movement in either case being suiiicient to carry the tooth of the pinion 44 free of the Wheel 48 before movin@ the pinion up or down. i i

Finally in the case of riveting machines, shapers and slotting machines, the pinion and the plate are out of engagement with each other, and 'consequently the tool does not rotate.

Having now described my invention what T claim as new and desire to secure by Letters Patent is y i l. An impact device/or hammer comprising a rotary shaft, a member fixed on the shaft and provided with a socket, a Weight slidably mounted in said socket, said socket being slotted, a pin on the Weight extending through said socket, a rotary guide on said pin and a cam cooperating with said guide for moving said Weight against the action of Vcentri'fugal force and for suddenly releasing the Same just before 'the moment of impact.

2. An impact device or hammer comprising a rotary member, an impact mass Vslidable radially thereof under the influence 0f centrifugal force, a guide memberV carried by said mass, a cam co-operating with sai-d guide member for restraining the centrifugal force and for suddenly releasing the same just before the moment of impact and means for throWinU said cam out of action Without stopping tlie machine.

An impact device or hammer comprising a rotary member, an impact mass slidable radially thereof under the influence of centrifugal force, a guide carried by said impact mass, an adjustable cam eo-operating with said guide for restraining the centrifugal force and for lsuddenly releasing'tlie same just before the .moment of impact and means for throwing said cam out of action Without stopping the machine.

4. In impact device or hammer comprising a frame, a member mounted for rotation on said frame, an impact mass slidable radially of said member under the iniuence of centrifugal force, a guide member on said impact mass, a cam co-operating with said guide member for restraining the centrifugal force and for suddenly'releasing the same just before the moment of impact,

and means for shifting said cam angularlyv of lsaid frame for varying the point of release, said means comprising a plate rotatably mounted in said frame, said cam being carried by said plate.

In testimony whereof I have signed -my name to this Specification.

NICOLAS GEORGEVITCH. 

